Miniaturization and cost-effectiveness are key directions in development of modern and next-generation networking and computing systems. Multilayer boards serve as main interconnect technologies in electronics devices constructed by means of chip, package and printed circuit board components. Besides that, interconnections are a base in forming passive components. Open-circuited and short-circuited planar transmission line segments of different forms and dimensions act as stubs, resonators, and other elements of passive components. A reason why the transmission lines have been used for such purposes is that these structures are well wave-guiding structures which can provide operation on a fundamental mode (for example, TEM or Quasi-TEM) with defined propagation constant and characteristic impedance in a wide frequency band.
Via structures formed by signal and ground vias conjointly can be not only vertical interconnections between planar transmission lines disposed at different conductor layers of the multilayer board but also as building blocks of passive components.
Japanese Laid Open Application JP 2008-507858 (US 2008/0093112A1) discloses composite via structures which can be used to design both open-circuited and short-circuited stubs and, as result, compact filtering components based on multilayer boards.
However, further dimensional reductions of passive components including filtering structures are necessary in a cost-effective manner for their application in next-generation computing and networking systems.
Also, it is important to obtain methods which can be used to control a bandwidth of filters.